Antenna



FIG. 1 is a front perspective view of an embodiment of an antenna showing our new design;

FIG. 2 is a front elevational view thereof, a rear elevational view being a same image thereof;

FIG. 3 is a top plan view thereof;

FIG. 4 is a bottom view thereof; and,

FIG. 5 is a right side elevational view thereof, a left side elevational view being a same image thereof. 

The ornamental design for an antenna, as shown and described. 